Detection of Mobile LoRa Jammers

Low Power Wide Area Networks (LPWANs) plat-forms (LoRa, NB-IoT, Sigfox) came to add a missing piece to the Internet of Things (IoT) ecosystem, namely long range communication in low power. LPWAN platforms are characterized by low data rate and long transmission time. LoRa specifically, has a data rate from 27 to 0.3 kbps and the transmission time of a single packet might be more than 1.5 seconds for some cases. These characteristics render LPWANs vulnerable to jamming attacks as a malicious user can perform a jamming attack from long range and the long transmission time is allowing a large time window to perform the attack. Moreover, if the jamming node is mobile (i.e., attached on a vehicle or an Unmanned Aerial Vehicle (UAV)), the current countermeasures proposed by the literature will not be relevant anymore. In this paper we investigate if it is possible to detect a mobile LoRa jammer based on the impact of the Doppler effect and based on a combination of signal strength and the entropy of the transmitted data. The results, obtained by utilizing commercial hardware, reveal that we could detect a potential mobile jammer that follows a deceptive jamming strategy with random payload, but further investigation is required for more sophisticated jamming attacks.